We have been researching 3D ground-truth systems for performance evaluation of vision and perception systems in the fields of smart manufacturing and robotics safety. In this paper we first present an overview of different systems that have been used to provide ground-truth (GT) measurements and then we discuss the advantages of physically-sensed ground-truth systems for our applications. Then we discuss in detail the three ground- truth systems that we have used in our experiments, the systems are: ultra wide-band, indoor GPS, and motion capture system. Finally, we discuss three different perception-evaluation experiments where we have used these GT systems.